Machine for cutting ties in venetian blind tapes having staggered straps



Jan 24, 1956 sc K 2,731,703

MACHINE FOR CUTTING TIES IN VENETIAN BLIND TAPES HAVING STAGGERED STRAPS Filed April 5, 1955 2 7 36 INVENTOR. EDWARD 50%4 AE United States Patent MACHINE FOR CUTTING TIES IN VENETHAN BLIND TAPES HAVING STAGGERED STRAPS Edward Schilke, Middletown, Conn. Application April 5, 1955, Serial No. 499,459 6 Claims. (Cl. 26-114) This invention relates to improvements in a machine of the type shown in my U. S. Patent No. 2,242,091, issued May 13, 1941.

As fully set forth in that patent, the machine is specifically adapted to cut the ties between the webs in Venetian blind tapes so that only the slat-supporting straps will extend between the webs.

As is well known, the supporting webs for a Venetian blind comprises two woven webs which extend vertically along the front and back, respectively, of the blind. The front and back webs are connected together by generally horizontal straps which extend between the webs adjacent their corresponding longitudinal edges. The blind slats rest upon the straps. in what is sometimes referred to as a single strap or single ladder tape, the straps are staggered along the opposite longitudinal edges of the webs and one slat will rest upon a strap adjacent one longitudinal edge of the webs and the next adjacent slat will rest upon a strap adjacent the other longitudinal edge of the webs. in what is sometimes referred to as a double strap or double ladder tape, the straps are arranged in pairs along the longitudinal edges of the webs and all of the slats rest upon two straps in each tape. The term ladder is used in that the front and rear webs appear similar to ladder rails and the straps appear similar to rungs.

As will be described in more detail hereinafter, the straps are formed by warp threads which are connected to the opposed webs by being woven therein at relatively distantly spaced locations along the webs. The said warp threads are also woven into the respective webs in relatively closely spaced locations, the connecting threads being called ties. In order that the webs can be separated so that the straps will hang horizontally, it is necessary to cut the tie threads. The improvement brought about by this invention is in a tie cutting machine which is particularly adapted for single ladder or single strap Venetian blind tapes. My co-pending application, Serial No. 499,449, filed of even date herewith, relates to an improvement in a tie cutting machine which is particularly adapted to cut the ties in a double ladder or double strap tape.

It is the general object of the invention to provide automatically operable means for applying tension to a Venetian blind tape when the tape is positioned on a tie cutting machine so that the ties will be accurately positioned and securely held in position for engagement by shears.

Other, more specific objects of the invention, as well as advantages thereof, will become apparent to those skilled in the art from the following specification taken in connection with the attached drawing, wherein Pig. 1 is a plan view of a single ladder Venetian blind tape;

Fig. 2 is a side elevational view thereof showing the front and back webs in closely spaced relationship and showing the tie connection therebetween;

Fig. 3 is a view similar to Fig. 2 but showing the tape after the ties between the Webs have been cut and after the webs have been separated;

Pig. 4 is a plan view of the tie cutting machine which incorporates the improvement of the present invention, the shears forming a part of the machine being shown in cutting engagement with the web ties; and

Fig. 5 is a view similar to Fig. 4, but showing the shears out of cutting engagement.

The single ladder Venetian blind tape 10 shown in Figs. 1, 2 and 3 comprises two woven fabric webs, namely, a top web 12 and a bottom web 14. The webs are shown in super-imposed relationship and as lying flat, the position of the webs as the tape is drawn through the tie cutting machine which will be described. However, when used to support the slats of a Venetian blind, the webs 12 and 14 will extend vertically, one web being located on the front side of the blind and the other web being located on the rear side of the blind. As is well known, the Venetian blind slats rest upon straps 16, 16 which extend between the webs 12 and 14. The straps 16, 16 are arranged in two rows extending along the respective longitudinal edges of the superimposed webs.

In accordance with conventional practice, the webs 12 and 14- and the straps 16, 16 are woven simultaneously. The straps 16, 16 are made up of warp threads which are not united by weft or filling threads but which are woven into the webs 12 and 14 at spaced apart locations along the longitudinal edges thereof. More specifically, the warp threads of the straps 16, 16 along the web 12 are woven therein at the places indicated by the reference numeral 18. The same warp threads are woven into the web 14- at the places indicated by the reference numeral 29. it will be observed that in weaving the Venetian blind tape 1Q with the webs 12 and 14 superimposed and closely adjacent one another, a woven place 18 on the web 12 is on one side closely adjacent one woven place 2t? on the web 14 and on the other side is spaced a substantial distance from another woven place 20. The distantly spaced woven locations 18 and 20 on the webs 12 and 14 are connected together by the warp threads making up the straps 16, 16. The closely spaced woven locations 13 and 20 on the webs 12 and 14 are connected by the same warp threads in what have been referred to as the ties designated by the numeral 22. The straps and ties are similarly formed along both longitudinal edges of the webs. It is important to observe that the straps and ties along one longitudinal edge of the webs 12 and 14 are staggered or interposed between the straps and ties located along the other longitudinal edge of the said webs.

When the ties 22, 22 are severed, as shown in Fig. 2, the webs 12 and 14 can be separated so that the straps 16, 16 extend therebetween as shown in Fig. 3 to receive and support the slats of a Venetian blind.

The machine for cutting the ties 22, 22 in the Venetian blind tape 10 is shown in Figs. 4 and 5 and is indicai generally by reference numeral 25. The entire machine is not shown. That is, the portions or elements of the machine 25 which are not necessary to an understanding of the present invention are not shown. However, referonce may be had to my Patent No. 2,242,091 for a complete disclosure of the parts not shown and the disclosure of that patent is incorporated herein by reference. The parts of the machine not disclosed in the attached drawing comprise the machine operating or driving mechanism.

As is more fully set forth in the aforementioned patent, the machine 25 has a table or bed comprising two longitudinally extending plates 26, 26 which are arranged in the same plane in side-by-side relationship with their inner longitudinal edges spaced apart, said plates being supported on frame structure including legs 27, 27. Suitable tape supporting structure is located between the portion thereof.

3 inner edges of the plates .26, 26 in one end portion of the table (the lefthandend portion as viewed in the drawing) and are tape 10 is advanced across the table between the plates 26, 26 from the tape supporting end As shown in the drawing, the tape advances from left to right.

:The means for engaging and advancing the tape comprise a lever 28 which is pivoted at 29 to a reciproca ing slide indicated generally by the numeral 39. it will be observed that the slide 35) is located between the plates 26, 26 and is arranged to be reciprocated longitudinally of the machine bed or table by the drive means (not shown). The-lever 28 has a hook 325 on its left-hand end and the lever is spring biased to normally locate its hook between the webs 12 and 14 from one longitudinal edge of the tape. When the hook 32 is disposed between the webs, it willengage a strap 16 and pull the tape it along with the slide 30 as the slide moves from left to right. When theslide -30 is moved toward the left, a cam following roller 33 on the free end of the lever 28 will engage a cam 34. The said cam is mounted on the machine so that it can be pivoted in the clockwise direction from the position shown but will not pivot in the counterclockwise direction and the cam is spring biased to the position shown. When the roller 33 engages the cam 34, the tape-engaging lever 23 will be pivoted on its axis 29 in a counterclockwise direction to disengage the hook 32 from the tape 10. As a result, when the slide has advanced toward the left to the position shown in Fig. 4, the roller 33 will be disengaged from the cam 34 and the tape-engaging lever 28 will assume the position shown wherein the hook will engage a strap. Then, when the slide 39 is moved toward the right, the tape will be moved therewith. Accordingly, as the slide 3% is reciprocated back and forth along the machine table, it will advance the tape toward the right the same distance during each complete cycle of reciprocation, resulting in step-by-step advance.

Means are provided in the machine structure for holding the tape after each step of advance. Such means includes a pivoted arm 35 which overlies the tape 1% adjacent the right-hand end of the machine and which pivots in timed relationship to slide reciprocation. That is, when the slide is moved toward the right with the tape-engaging lever 28 pulling the tape along, the arm 35 is elevated to a position out of engagement with the tape. When the slide reaches the right-hand end of its stroke, the arm 35 is pivoted intoengagement with the tape to hold the same in its advanced position while the slide moves toward the left to effect another engagement with the tape.

In each step in the advance of the tape 10 along the machine 25, the said tape is positioned on the machine table so that the adjacent ties 22, 22 on opposite longitudinal edges of the tape are positioned for engagement by two pairs of shears 36, 36 which are located in opposed and offset relationship adjacent the longitudinal edges of the tape. It will be observed that the shears are the scissors type and have substantially identical operating elements which are indicated by the same reference numerals. It will also be seen by comparison of Figs. 4 and that the shears are operated to move into and then out of position between the webs of the tape. That is, the shears are inserted between the webs i2 and 14 to cut the ties and are then moved away from the tape so the tape can be advanced.

The operating structure for ,each pair of shears 36 comprises a lever 37 which is pivoted at 38 to the machine table, one end portion of the lever supporting the pivot pin for the shears and the other end of the lever supporting a cam following roller 39. The lever 37 is spring biased to shear retracted position wherein the roller 39 is positioned for engagement .by a cam block 4%) sup ported on the slide 30, there being one such cam block on each side of. theslide-Sl) for engagement with the respeetive rollers 39, 39. When the slide 30 is moved toward the left to the positignshown in Fig.4, the. cam block 40 will pivot the shears lever 37 so as to move the shears into the tape 10 between the webs 12 and 14. When the slide moves toward the right to the position shown in Fig. 5, the shears lever will be spring biased to retract the shears.

Also during left-hand movement of the slide 36, the cam blocks 40, 40 will engage rollers 41, 41 on spring biased levers 4-2, 42 each of which carries a shears closplate 43 on its other end. The shears closing plates engage the ends of-screws 44, 44 which are adjustably secured to the scissors arms of the respective shears 36, 36. When the cam blocks 40, 4t) engage the rollers 41, 41, the levers .42, 42 are pivoted and as a result, the closing plates 43, 43 are shifted toward the left to close the scissor arms of the respective shears 36, 36. When the slide moves to the right, the levers 42, 42 are biased to permit the shears to open.

it will be observed that the shears moving levers 37, 37 are first pivoted by the cam blocks 40, 40 to insert the shears between the webs and then the shears closing levers 42, 42 are pivoted to effect closing of the shears. Obviously, as the shears close, the ties 22, 22 are cut.

A plurality of pivoted levers, all of which are indicated by the reference numeral 45, are located on the machine bed adjacent the. opposite longitudinal edges of the tape. The levers 45, v45 are. spring biased to the positions shown but are capable of being pivotedout of the position shown by the straps 16, 16 as the tape is advanced from left to right. It is the purpose of the levers 45, 45 to separate the webs 12 and 14 sufliciently for free movement or" the shears 36, 36 into and out of engagement with the ties 22, 22.

In addition to the aforementioned levers 45, 45, the machine of the present invention is provided with a pivoted stop 46 which will engage the straps 16, 16 along one longitudinal edge of the tape 10 to apply tension to the tape. Morespecifically, the pivoted stop 46 engages a strap 16 and biases the tape Iii-toward the left in opposition to the tape restraining force applied by the pivoted arm 35. The tension applied to thetape is for the purpose of assuring that the ties 22, 22 between the stop 46 and the hook 32 .will be properly located'for cutting engagement by the shears 36, 36.

The means operating the stop 46 include an extension 47 on the shearsend of the lever 37 for the left-hand shears 36. An arm 48 is fixedto the end of the lever extension 47 and supports a spring biased plunger 49. It will be observed that when the shears are inserted between the webs, the lever extension 47 is pivoted to bring th plunger 49 into engagement with an arm 50 on the stop 46, such engagement causing the stop 46 to pivot in a counterclockwisedirection to bring a tension pin 51 into engagement with a strap 16 applying tension, to the tape 10. The extent .of counterclockwise rotation of the stop 46 is limited by astop pin 52 and the amount of tension applied to the stop 46 is determined by the tension of the spring 53 which engages the plunger 49.

It has been found that the pivoted stop 46, which is engaged by the plunger carried on the arm secured to the shears lever extension will give every assurance that the ties 22, 22 are properly positioned for cutting by the shears 3.6, 36. Before incorporation of the stop 46, it was possible for the ties 22, 22 to be improperly positioned for cutting. That is, when the tape was advanced, there was the possibility that inertia or backlash caused by tape movement wouldimproperly position the ties. It has been found that the stop is so accurate and enhances the machine operation to a point where inspection of the cut tapes is practically upnecessary.

It l be un e stand tha alte t ns and changes m y be made in the essshiss With n .th r its d S p o the present invention. Therefore, the details of structure as described are not intended to define the invention, the following claims being relied upon for that purpose.

I claim as my invention:

1. In a machine for cutting the ties in a Venetian blind tape comprising a pair of elongated superimposed webs which are connected by threads forming the ties and the slat-supporting straps and wherein the machine includes a table, a slide reciprocable along the table and having means engageable with the tape to advance the same in one direction during movement of the slide in said one direction, means engageable with the tape to hold the same while the slide moves in the opposite direction, and cutting means operatively associated with said slide and constructed and arranged to be inserted between the webs to cut a tie during movement of the slide in said opposite direction, the improvement comprising a stop operatively associated with said slide and constructed and arranged to engage said threads between the webs and to apply force to the tape in said opposite direction when the cutting means is inserted between the webs to cut a tie, the said force being applied to position a tie for engagement by the cutting means.

2. In a machine for cutting the ties in a Venetian blind tape comprising a pair of elongated superimposed webs which are connected by threads forming the ties and the slat-supporting straps and wherein the machine includes a table, a slide reciprocable along the table and having means engageable with the tape to advance the same in one direction during movement of the slide in said one direction, means engageable with the tape to hold the same while the slide moves in the opposite direction, and cutting means operatively associated with said slide and constructed and arranged to be inserted between the webs to cut a tie during movement of the slide in said opposite direction, the improvement comprising a pivoted stop which is operatively associated with said slide and arranged to be moved thereby between the webs into engagement with the threads to apply force to the tape in said opposite direction when the cutting means is inserted between the webs to cut a tie, the said force being applied to position a tie for engagement by the cutting means.

3. In a machine for cutting the ties in a Venetian blind tape comprising a pair of elongated superimposed webs which are connected by threads forming the ties and the slat-supporting straps and wherein the machine includes a table, a slide reciprocable along the table and having means engageable with the tape to advance the same in one direction during movement of the slide in said one direction, means engageable with the tape to hold the same while the slide moves in the opposite direction, and cutting means operatively associated with said slide and constructed and arranged to be inserted between the webs to cut a tie during movement of the slide in said opposite direction, the improvement comprising a movable stop, stop operating means operatively associated with said slide and including a spring biased plunger engageable with the said stop to position the same between the webs in engagement with said threads to apply force to the tape in the said opposite direction when the cutting means is inserted between the webs to cut a tie, the said force being applied to position a tie for engagement by the cutting means.

4. In a machine for cutting the ties in a Venetian blind tape comprising a pair of elongated superimposed webs which are connected by threads forming the ties and the slat-supporting straps and wherein the machine includes a table, a slide reciprocable along the table and having means engageable with the tape to advance the same in one direction during movement of the slide in said one direction, means engageable with the tape to hold the same while the slide moves in the opposite direction, and cutting means operatively associated with said slide and constructed and arranged to be inserted between the webs to cut a tie during movement of the slide in said opposite direction, the improvement comprising a stop pivotally supported on the table adjacent one longitudinal edge of the tape and movable into and out of position between the webs, and a lever pivotally mounted on the table having a spring biased plunger supported on one end which plunger is engageable with the said stop to resiliently urge the same between the webs, the other end of said lever being engageable by the slide during movement thereof in said opposite direction to cause engagement of the plunger with the stop, the said lever being located on the table to cause said stop to engage the threads between the webs and thereby to apply force to the tape in said opposite direction when the cutting means is inserted between the webs to cut a tie, the said force being applied to position a tie for engagement by the cutting means.

5. In a machine for cutting the ties in a Venetian blind tape comprising a pair of elongated superimposed webs which are connected by threads forming the ties and the slat-supporting straps and wherein the machine includes a table, a slide reciprocable along the table and having means engageable with the tape to advance the same in one direction during movement of the slide in said one direction, means engageable with the tape to hold the same while the slide moves in the opposite direction, and a lever pivotally mounted on the table and supporting cutting means for movement into and out of position between the webs which lever is engageable by the slide to position the cutting means between the webs when the slide moves in said opposite direction, the improvement comprising a movable stop operated by said lever and constructed and arranged to engage said threads between the webs and to apply force to the tape in said opposite direction when the cutting means is moved into position between the webs, the said force being applied to position a tie for engagement by the cutting means.

6. In a machine for cutting the ties in a Venetian blind tape comprising a pair of elongated superimposed webs which are connected by threads forming the ties and the slat-supporting straps and wherein the machine includes a table, a slide reciprocable along the table and having means engageable with the tape to advance the same in one direction during movement of the slide in said one direction, means engageable with the tape to hold the same while the slide moves in the opposite direction, and a lever pivotally mounted on the table and supporting cutting means for movement into and out of position between the webs which lever is engageable by the slide to position the cutting means between the webs when the slide moves in said opposite direction, the improvement comprising a stop pivotally mounted on the table adjacent one longitudinal edge of the tape for movement into and out of position between the webs, resilient means on said lever engageable with said stop to position the same between the webs to engage the threads and apply force to the tape in said opposite direction when the said lever moves the cutting means into position between the webs, the force being applied to position a tie for engagement by the cutting means.

References Cited in the file of this patent UNITED STATES PATENTS 2,242,091 Schilke May 13, 1941 

